DE102017008773A1 - Cooling process for process control for evaporators - Google Patents

Abstract

In order to separate a component from a medium (a solution mixture) with other components, an evaporator arrangement can be used in which a component of the liquid form is transferred to the gas phase, while other components remain in the medium. For this, the parameters of pressure and temperature, which essentially determine an evaporation process, must be suitably adjusted and / or regulated, and the resulting vapor must be cooled so that it can condense and the condensate can be collected. In evaporators existing in the prior art, this increases Steam from below into a cooling area in which a cooling coil, through which a coolant flows, should provide for the cooling, but which also belongs to a vacuum region (vacuum), in which the passively flows in steam, so that tries slightly exaggerated By passing the steam in the reverse direction (from top to bottom) and through functionally switched areas so that the steam is now passed through the interior of the cooling coil (in which coolant has previously flowed) and the coolant now in the outer space the cooling coil lingers (which previously belonged to the vacuum area), the Küh Damping made more efficient and the distillate recovery are accelerated. Improved and efficient evaporation process for many evaporator arrangements, for. for rotary evaporators with improved distillate formation.

Description

The invention relates to a method for separating at least one liquid component from a medium (for example a mixed solution) and / or for purifying or concentrating a liquid in which other components (eg solvents) are contained or for the recovery of liquid components when drying and / or concentrating solid or liquid components escape or are dissolved or emulsified in a liquid component.

By first separating at least one component from other constituents of the medium by evaporating at least one component, while the other components remain in the medium, after cooling the steam in a cooling zone separate from the evaporation space (or drying space), this component can be recovered in liquid form become.

In this context, the invention relates in particular to a method and an arrangement for cooling for vaporous media which arise during such evaporation.

• - einem Verdampfungsgefäß mit einen Verdampfungsraum, in den das zu verdampfende Medium eingebracht wird,
• - mindestens einer Möglichkeit, im Verdampfungsgefäß die Druckdifferenz zwischen dem Inneren des Mediums und dem Gasdruck über dem Medium einzustellen (Einstellung des Drucks),
• - mindestens einer Möglichkeit, das Medium auf eine Prozesstemperatur zu erwärmen (Einstellung der Temperatur),
• - meist einer Möglichkeit, das Medium während des Verdampfens zu rühren,
• - notwendigerweise einer Möglichkeit, den bei der Verdampfung entstehenden Dampf vom Ort der Entstehung abzutransportieren,
• - in einen Bereich, in dem die Möglichkeit besteht, diesen Dampf zwecks Kondensation zu kühlen und
• - das so entstehende Destillat als Produkt der Verdampfung aufzufangen,

wobei die tatsächlichen technischen Ausführungen sehr unterschiedlich sein können.In order to be able to set and / or regulate the process parameters for the execution of an evaporation on the surface of the medium (the actual process location), technical evaporation arrangements of the evaporators in focus here are generally (ia) made out

• an evaporation vessel having an evaporation space into which the medium to be evaporated is introduced,
• at least one possibility of setting in the evaporation vessel the pressure difference between the interior of the medium and the gas pressure above the medium (setting of the pressure),
• at least one way of heating the medium to a process temperature (setting the temperature),
• most often a way to stir the medium during evaporation,
• necessarily a possibility to carry off the vapor produced during the evaporation from the place of origin,
• - In an area where there is the possibility to cool this steam for the purpose of condensation and
• - to capture the resulting distillate as a product of evaporation,

wherein the actual technical versions can be very different.

• - der Rotationskolben eines Rotationsverdampfers oder
• - ein Erlenmeyerkolben oder ein Becherglas (mit geeignetem Deckel) auf einem Magnetrührer oder
• - ein Topf (mit geeigneten Deckel) auf einer Herdstelle.

Although it is irrelevant which evaporation vessels are used (of course, target quantities determine the size of the vessels), here can be seen as evaporation vessels:

• - The rotary piston of a rotary evaporator or
• - an Erlenmeyer flask or a beaker (with a suitable lid) on a magnetic stirrer or
• - a pot (with a suitable lid) on a stove.

Among other things, the invention therefore also relates to rotary evaporators with a rotatable, e.g. on a tripod element suspended rotary evaporating flask (hereinafter only rotary piston), which can be set by a motor drive in rotating motion and immersed in the prior art in a heating bath. Due to the heated heating bath, the temperature of the medium is set to the required process temperature.

Therefore, while the invention is described essentially (i.W.) using the example of the construction of a rotary evaporator, it is not limited to rotary evaporators.

Above the liquid in the rotary piston i.a. In addition, a negative pressure (which is referred to as vacuum) is produced, which specifies the evaporation parameter "pressure" suitable for the evaporation process, but at the same time also responsible for the removal of the resulting vapor from the evaporation region of the rotary piston. The lower this pressure, the sooner a liquid evaporates, but the pressure must be set so that not all the other liquid components contained in the solution mixture evaporate at the same time.

In order to set the negative pressure, however, the entire volume area connected to the rotary piston must be pumped out by a vacuum pump to the desired negative pressure value. This vacuum area is relatively large and includes i.W. the proportion of space in the rotary flask, which is not occupied by the medium to be evaporated, the steam transmission area, the entire, in the prior art towering radiator area and the space area in which the distillate / condensate is collected. I.a. an effective vacuum pump can be provided with a suitable control, so requires a considerable effort.

Due to the pressure gradient generated by the vacuum pump and the vapor from the evaporation area in the direction of a cooling area transported with a suitable cooling device, where a means for collecting the distillate is provided. In the prior art, this cooling device is generally a cooling coil in the form of a spirally wound tube (coil), through which a coolant is passed.

In an evaporation process, the parameter combination "pressure above the liquid" with respect to "pressure in the liquid mixture" and the temperature directly at the liquid surface (ie at the location of the physical event) essentially determine the evaporation process and also its efficiency; but i.a. always given only as a process parameter pair (P, T) and determining the process. An achievable with a technical arrangement separation success is therefore given for certain separation tasks only with appropriate (P, T) parameter pairs. The parameters to be set are empirical values that belong to process knowledge; Physicochemical knowledge is at least helpful; the parameters and coefficients that can determine the process may i.a. Tables (e.g., Dortmunder database).

Evaporation also takes place at the surface of a medium even at low temperatures and at a high ambient air pressure, and a portion of the resulting vapor always goes back into the liquid phase. The ratio of these two simultaneous and countercurrent operations, in conjunction with the rate of arrival and departure, ultimately also determines the amount of evaporation, i. the evaporation success. At a particular given temperature, the ratio between the pressure in the subsurface medium and the pressure in the vapor above that surface determines the evaporation success, i. How much material changes from the liquid phase to the vapor phase, but also how much steam returns to the liquid phase. This applies to each of the components contained in the solution mixture, but each with a different speed and equilibrium position. Steam from a technically carried out evaporation, therefore, will never be completely free from other components of the liquid mixture. But at a given temperature and at a given pressure (both set as a process parameter), this is done at an equilibrium point that is different for each component in the medium.

This circumstance is the reason why the distillate or condensate resulting after cooling, which arises in the vacuum region and drips downwards by gravity into a distillate vessel, can also re-evaporate, for which very complex countermeasures have been described in the prior art.

If a component evaporates on a liquid surface, this will change both the mixture or the mixture concentration, as well as the temperature (by evaporative cooling) and the pressure (by gas / vapor formation) directly at this surface. These changes of individual components and parameters affect the evaporation process itself again. The concentration of the most easily evaporating component may be slightly different (lower by evaporation) directly at the surface of the medium than slightly deeper inside the medium. Therefore i.a. mass transport (e.g., diffusion, mixing, stirring, etc.) replace the surface material with material from the interior of the liquid having the original mixing ratio there.

Here, a rotary evaporator has the advantage that a mass transport or exchange is always carried out by the rotation of the piston, at least the medium is replaced at the surface quite quickly by medium from the inside.

In the case of a rotary evaporator, a liquid film forms on the glass of the piston inner surface by adhesion above the medium to be vaporized therein, which is renewed and updated over and over again by the rotational movement. This liquid film is additionally vaporized on the (upper) glass wall, which can positively support the evaporation process. That is, a (rotating) rotary piston has the advantage that it achieves both a rapid exchange or thorough mixing of surface material and inner material, as well as a larger surface for the evaporation.

However, an exchange or thorough mixing of surface material and inner material can also be achieved by other stirring mechanisms.

Many parameters determine the success of a separation task and can decisively determine the result of a separation performed with an apparatus, which often only reaches a more or less large concentration shift. The knowledge of the effect of certain parameters and their use in an arrangement may therefore make u.U. First, the properties and the technological advantage of evaporator arrangements, but rather by experience, as determined by clearly defined and well-defined table values.

For example, in a rotary evaporator it is not exactly defined how large the ratio of the "evaporation directly on the surface of the liquid to be evaporated in the medium Rotary piston "for" evaporation through the liquid film on the surface of the piston inner wall above the medium to be evaporated "in a running process is really. This ratio determines, inter alia, the evaporation result and the achievable separation quality, but is not only characterized by simple geometric relationships: the surface of the liquid surface in the rotary piston is approximately a circular area F _circle = πr ² , the surface of the inside of the glass wall above this liquid surface is approximately ( approximately) a hemisphere with half the surface of the ball F _ball = 4πr ² . One could therefore assume that in a rotary evaporator, in which there is an approximately 1.7 times larger surface than the beaker, the evaporation success is correspondingly greater. However, this is not the case: the surface of the piston inner wall above the medium to be evaporated, for example, has no constant temperature, because the temperature of the glass inner wall surface decreases in the direction of rotation on the circumference of the glass bulb by the evaporative cooling; depending on the size of the heat capacity and the thermal conductivity of the glass more or less. In addition, the wetted surface is dependent on the filling quantity, which changes with time (evaporation-related) and by evaporation itself.

• - der Dampf nicht in die Vakuumpumpe gelangen darf und
• - zudem eine Rückverdampfung des Destillats vermieden werden muss.

Also, the area or space in which the cooling takes place in the prior art is full of "confusion". A stronger vacuum creates a stronger suction pressure for the steam generated in the evaporation space, which increases faster in the cooling space, whereby more steam condenses and drips as a distillate, which meets the goal (more distillate). On the other hand, the source of the vacuum (a "vacuum pump") must provide only limited or regulated performance because

• - the steam must not enter the vacuum pump and
• - In addition, a re-evaporation of the distillate must be avoided.

Therefore, with regard to the respective cooling arrangement, a "supply" of the vacuum is connected as far as possible at the top of the cooling tower; one always tries to keep the upper cooling area or the upper area of the cooling coil free of steam by suitably setting the power of the vacuum pump. However, allowing the vapor to rise only to a defined altitude is a difficult task under the given conditions with many variable parameters. The larger the space in which a defined negative pressure is to be produced, the more difficult it becomes i.a. also to achieve this with a pressure control by the vacuum pump.

In a constantly proceeding process, a number of physical processes run parallel in time, which can not be considered individually, because processes, and their influence on various parameters, mutually influence each other, can amplify and hinder each other and even stabilize themselves (through negative feedback) ,

• - Wenn Flüssigkeit verdampft, wird dazu Energie benötigt, die der Temperatur der Flüssigkeit entzogen wird; Verdampfung bewirkt also eine Abkühlung unmittelbar an der Flüssigkeitsoberfläche, was den Verdampfungsprozess verlangsamt, und
• - wenn eine Flüssigkeit verdampft, entsteht unmittelbar über der Flüssigkeitsoberfläche Dampf. Die Dichte des entstehenden Dampfes (Dampfmenge, Konzentration, Dichte) wird unmittelbar über der Flüssigkeitsoberfläche am größten sein, der (Gas-) Druck wird also unmittelbar über der Flüssigkeitsoberfläche größer sein. Die Verdampfung bewirkt somit auch über eine Druckerhöhung die Verlangsamung der Verdampfung; die Geschwindigkeit, mit der entstehender Dampf (durch das eingestellte Vakuum) abtransportiert wird, ist hier mit entscheidend.

In the evaporation chamber, which itself is part of the vacuum space, applies, for example:

• - When liquid evaporates, this energy is needed, which is removed from the temperature of the liquid; Evaporation thus causes a cooling directly on the liquid surface, which slows down the evaporation process, and
• - When a liquid evaporates, steam is generated immediately above the surface of the liquid. The density of the resulting vapor (amount of vapor, concentration, density) will be greatest immediately above the liquid surface, so the (gas) pressure will be greater immediately above the liquid surface. The evaporation thus causes a pressure increase, the slowing down of the evaporation; the speed at which the resulting steam is removed (by the set vacuum) is decisive here.

Thus, parameters also become secondary, e.g. the vacuum setting, which is intended to determine the pressure and the pressure gradient across the surface of the liquid, but also determines the removal of the vapor.

The "temperature supply", i. a heat energy transport, is determined in a rotary piston by the respective heating power, by the immersion depth of the rotary piston in the heating bath or by Heizbadhöhe and the plunge angle and also by the filling height of the medium in the rotary flask, e.g. even on the (varying) length of the active cooling area on the cooling coil (the steam rising height), which itself depends on the gas pressure, from the coolant passing through the inside of the cooling coil, from its temperature, from the heat transfer resistance from the steam to the coolant etc.

In prior art arrangements, process parameters (not just in an assembly such as a rotary evaporator) remain stable over an extended period of time when the overall evaporation process, with subsequent cooling, is consistently uniform throughout.

With a suitable design of the evaporation arrangement, medium supply, heat, the cooling in the cooling area and the (under) pressure generation (in the state of the art generally by suction of air or gas) by constantly held flow rates for stable conditions over the surface of the medium to be evaporated.

• - Weit entfernt von der Flüssigkeitsoberfläche (dem eigentlichen Prozessort) stellt eine Wärmequelle Wärmeenergie bereit, so dass entlang eines Weges von der Wärmequelle bis zur Oberfläche des Mediums ein Temperaturgefälle und ein Wärmefluss entsteht, wodurch an der Oberfläche des Mediums eine definierte Prozesstemperatur entsteht, die bei stabil laufendem Prozess zumindest in etwa stabil aufrechterhalten werden kann.
• - Weit entfernt von der Flüssigkeitsoberfläche (dem eigentlichen Prozessort) stellt eine Pumpe einen Unterdruck her, so dass entlang eines Weges (von der Oberfläche des Mediums bis zur Vakuumquelle) ein Druckgefälle entsteht, wodurch über der Oberfläche des Mediums ein definierter Prozessdruck erzeugt wird, der bei stabil laufendem Prozess zumindest in etwa stabil aufrechterhalten werden kann.
• - Eine Einstellung von Sollwerten an der Vakuumpumpe und an der Heizungsregelung erfolgt eher aus der Erfahrung heraus, weniger an Hand definierter „Tabellenwerte“; man dreht einfach solange an den Maschinen-Einstellungen herum, bis „es stimmt“. Irgendwann werden stabile Prozessbedingungen für einen stabil ablaufenden Verdampfungsprozess erreicht und die an einer konkreten Verdampfungsanordnung benötigten Einstellungen gehen in das Prozesswissen des jeweiligen Betriebs ein.
• - Damit sowohl der Druck über der Oberfläche, als auch die Temperatur im Medium sich nicht aus einem laufenden Prozessgeschehen herausbewegen, darf bei stabilen sonstigen Parametern (wie z.B. die Rotations-Drehzahl des Rotationskolbens) i.a. nur ein stetiger und i.a. genau definierter (Mittel-)Wert an Verdampfung eingestellt sein.
• - Die jeweilige Kühlung des erzeugten, dem Druckgefälle des Vakuums folgenden, in den Kühlbereich aufsteigenden Dampfs muss so effizient sein, dass dieser Dampf nicht ganz im Kühlturm aufsteigen kann und in die Vakuumpumpe gelangt.

The basic procedure to be found in the prior art can be summarized by way of example for a rotary evaporator as follows:

• - Far from the liquid surface (the actual process location), a heat source provides heat energy, so that along a path from the heat source to the surface of the medium, a temperature gradient and heat flow is created, creating a defined process temperature at the surface of the medium, the stable running process can be maintained at least approximately stable.
• - Far from the liquid surface (the actual process location), a pump produces a negative pressure, so that along a path (from the surface of the medium to the vacuum source) creates a pressure gradient, whereby over the surface of the medium, a defined process pressure is generated can be maintained at least approximately stable at stable running process.
• - An adjustment of set points on the vacuum pump and on the heating control is rather based on experience, less on hand defined "table values"; Just turn around the machine settings until it's "right". At some point, stable process conditions for a stable evaporation process are achieved and the settings required for a specific evaporation arrangement are included in the process knowledge of the respective operation.
• - In order to ensure that both the pressure above the surface and the temperature in the medium do not move out of an ongoing process, with stable other parameters (such as the rotational speed of the rotary piston) generally only a continuous and generally well-defined (middle) Value to be set to evaporation.
• - The respective cooling of the generated, the pressure drop of the vacuum following, rising into the cooling area steam must be so efficient that this steam can not rise completely in the cooling tower and enters the vacuum pump.

• - die Füllhöhe des Mediums im Rotationskolben
• - die Rotationsgeschwindigkeit des Rotationskolbens,
• - die Eintauchtiefe des Rotationskolbens in das Heizbad (bzw. die Heizbadhöhe),
• - die Vakuumerzeugung und die Stärke des Unterdrucks,

weil jeder dieser Parameter das Fließgleichgewicht der mengenartigen Größen mitbestimmt; sogar die Temperatur des Destillats ist zu beachten.A stable evaporation process is in a flow equilibrium, in which other variable parameters must be kept stationary stable, such as

• - The filling level of the medium in the rotary flask
• the rotational speed of the rotary piston,
• the immersion depth of the rotary flask in the heating bath (or heating bath height),
• - the vacuum generation and the strength of the negative pressure,

because each of these parameters determines the flow equilibrium of the quantity-like quantities; even the temperature of the distillate is to be considered.

The process parameters to be set for the target evaporation process are known and can be manipulated with suitable engineering arrangements, e.g. adjusted, controlled and / or regulated. The resulting steam must be removed as quickly as possible, but at a constant flow rate. The cooling and vacuum generation must also be constant.

• - zum einen für die Temperatur bzw. Wärmeenergie (als erste mengenartige Größe),
• - zum anderen für den Abtransport von Dampf von den Innenkolben-Oberflächen weg durch das eingestellte Vakuum (dieser Abtransport erfolgt passiv und ist u.U. ausgesprochen langsam)
• - und auch für den Kühlbereich, der zu optimieren ist.

With regard to the physical process, one can include several flow rates or flow cycles in the considerations, all of which must be in a process equilibrium. That is true

• - on the one hand for the temperature or heat energy (as a first quantity-like quantity),
• - on the other hand for the removal of steam from the inner piston surfaces away by the set vacuum (this removal is passive and may be extremely slow)
• - And also for the cooling area, which has to be optimized.

In a multifactorial process, it is i.a. difficult to want to stably adjust the process by regulation and / or control of only one or two individual parameters and / or to achieve only a reasonably optimal setting at all. In addition, i.a. also the framework conditions.

An evaporation success will be as good as always; but that this is optimal, can rarely be achieved or proven. No matter how the temperature and pressure (vacuum) will be adjusted, the most volatile component of a mixed solution will almost always be most abundant in the distillate and the remainder in the evaporator flask will be least likely to contain the most volatile component. Only an accompanying chemical analysis can show how effective the respective evaporation success is and how it is to be evaluated.

This applies not only to the special constructions of rotary evaporators, but also to all other processes used to evaporate media and to all forms of technical evaporator arrangements. Evaporation arrangements that can be assembled with simple laboratory means are not so ineffective in this sense.

Against this background, it is an object of the invention to provide a method for the simplest possible process control for the evaporation of media for the purpose of component separations and in particular to achieve this by an improved design of the cooling area of a technical evaporation arrangement and to improve the evaporation performance.

This object is achieved with the characterizing details of claim 1.

In particular the fact that not (as usual in the prior art) of the pressure gradient of the vacuum following, in the cooling area (the cooling tower) rising steam is cooled at existing negative pressure by a cooling coil with cooling medium, but the extracted steam inside a (structurally comparable) Cooling coil is transported under increasing compression and cooled, wherein for cooling a coolant flows around the cooling coil from the outside.

• eine Darstellung des physikalischen Hintergrunds der Erfindung zur Einstellung des Drucks.
• stellt als Beispiel einen Rotationsverdampfer zur grundsätzlichen Übersicht und Beschreibung der Erfindung dar.
• zeigt für einen solchen Rotationsverdampfer eine Vorrichtung zur Abkühlung des entstehenden Dampfs auf dem Stand der Technik.
• zeigt eine erste erfindungsgemäß umgerüstete Verdampfungsanordnung auf der Basis eines Rotationsverdampfers.
• zeigt eine zweite erfindungsgemäß umgerüstete Verdampfungsanordnung, bei der mit Gleichrichtungs- bzw. Einwegventilen mittels einer speziellen Zylinder-Kolben-Pumpe der Dampfabtransport aktiv betrieben werden kann.

The method will be explained with reference to the accompanying drawings. This shows the

• a representation of the physical background of the invention for adjusting the pressure.
• is an example of a rotary evaporator for a general overview and description of the invention.
• shows for such a rotary evaporator, a device for cooling the resulting vapor in the prior art.
• shows a first inventively retrofitted evaporation arrangement based on a rotary evaporator.
• shows a second inventively retrofitted evaporation arrangement, in which can be actively operated with rectification or one-way valves by means of a special cylinder-piston pump, the steam removal.

Initially, an evaporation arrangement according to the invention gives way (cf. ) characterized by the prior art, that according to the invention the respectively used evaporation vessel ( 50 ) (as a first vessel, in a rotary evaporator, the rotary flasks) in a medium circuit between a second vessel ( 33 ) is supplied from the medium to the evaporation vessel ( 34 ), and a third vessel ( 32 ), which receives medium removed from the evaporation vessel ( 35 ). By at least one vessel alone or in combination with another vessel is adjustable in height by the vessels involved and / or by the overlying the medium in the second other and / or in the third other vessel pressure is adjustable or can be controlled in various ways and Way the pressure difference across the liquid surface in the evaporation vessel for process control are relatively easy to set or regulated.

This eliminates the need to maintain the process pressure at a defined value solely by setting or controlling a vacuum pump.

It is noteworthy that the volumes, which, mind you, are to be included in the second and third vessels for a process control in the evaporation vessel are much smaller than the volume above the liquid level in the evaporation vessel (the volumes at the process location can be almost arbitrarily large). , A regulation of the pressure of small volumes is possible so quickly and efficiently and also with little effort, a process control is much faster with the inventive method than can be achieved with a vacuum control over the liquid to be evaporated in the prior art.

It is particularly noteworthy that such vaporization can also be carried out with arrangements that do not even have to be specifically designed for it (as is the case, for example, with a rotary evaporator, which is specially designed for this purpose). Also with commonly available vessels, such as e.g. a saucepan on a hotplate, an Erlenmeyer flask or beaker on a heatable magnetic stirrer or even with very large vessels, that is, practical vessels from the small laboratory or kitchen to large scale industry (e.g., reactors) arrangements, the method can be usefully employed and utilized.

shows the physical background to illustrate this aspect: Two vessels ( 10 ) ( 11 ) with medium which, with respect to their liquid levels ( 17 () 18 ) the relative height h ( 12 ) and to the liquid level ( 14 ) of the medium in an evaporation vessel ( 13 ) the height differences h ₁ ( 15 ) and h ₂ ( 16 ) exhibit. The medium in the upper vessel ( 10 ) is with a hose ( 19 ) with the medium ( 20 ) in the evaporation vessel ( 13 ) directly connected, the medium ( 20 ) in the evaporation vessel ( 13 ) again with the medium in a lower vessel ( 11 ). The hose guide ( 19 ) ( 21 ) is completely arbitrary.

In such coupled together vessels ( 10 ) ( 20 ), flows from the upper vessel ( 10 ) Following the medium of gravity down first into the medium ( 20 ) in the evaporation vessel ( 13 ). The drive for the flowing medium are pressure differences which are determined by a hydrostatic pressure and by the pressure above the respective liquid levels (P = P ₀ + h _i * ρ * g). The amount of flowing medium is limited by the resistance of the hose system, so it is also determined by the thickness of the pipes. Regardless, however, the pressure in the system at a certain level ( 14 ) determined only by height differences: In not too fast flowing medium is in an arrangement of the the pressure at each point only by the respective height h or by the height differences h ₁ ( 15 ) or h ₂ ( 16 ) certainly.

This lawlessness is independent of how the path that the medium may have to take is designed (cf. ). However such a way is determined by a hose guide that can be arbitrarily entangled and knotted, only the height differences h ₁ ( 15 ) h ₂ ( 16 ) and overall H ( 12 ) and the (gas) pressure above the liquid surfaces determine the pressure differences given in this arrangement. This is also the pressure on the surface of the medium ( 14 ) in the intermediate vessel ( 13 ) determined only by these height differences (an incompressibility of the liquids is given).

Each of the vessels ( 10 ) ( 11 ) ( 20 ) can be determined by height adjustment, the pressure conditions in the overall arrangement and especially for the standing in the middle vessel (in which, for example, the actual evaporation process to take place). The pressure in the medium ( 20 ) of the tundish can therefore by a height adjustment of the two vessels ( 10 ) ( 11 ) alone or together and / or by the adjustment of the gas pressure, which prevails over the respective liquid, in each case be adjusted. In controlling the process over the pressure conditions in the vessels ( 10 ) ( 11 ) could in principle account for the regulation by a height adjustment also. With this (cf. ), the pressure difference between the interior of the liquid ( 54 ) and above ( 50 ) of the liquid surface ( 55 ) can be easily adjusted or regulated, because of the small volumes much faster than in the prior art.

However, how the pressure regulation in the case of an evaporation arrangement ultimately takes place can not be significant here. This can be done in any other way as well and also correspond to the prior art, for example by means of a pressure control over the room ( 50 ) of the medium ( 54 ) of the rotary piston.

Here, the pressure setting can be assumed as given, but the necessary components are in the context of the to be considered again: shows a rotary piston ( 50 ) of a motor-driven rotary drive ( 51 ) can be set in rotation about its longitudinal axis and a vapor passage for the resulting in the rotary piston steam ( 31 ) having. The steam passage is here also passage for two lines; one ( 53 ) through which medium is supplied to the rotary piston and a ( 52 ), through which medium is discharged from the rotary piston.

The evaporation takes place in the rotary flask in the evaporation chamber ( 50 ) (hereinafter only vapor space) above the medium ( 54 ) instead of. The capacity of the medium ( 54 ) determines the position and height of the liquid level at a given (mechanical) setting and setting the piston height ( 55 ).

• - die „Vakuumerzeugungszone (30)“, die i.a. oberhalb eines Dampfabkühlungsbereichs (31) liegt,
• - der Destillat-Sammelbereich (40), der unterhalb des Dampfabkühlungsbereichs (31) liegt,
• - der Bereich der Dampfdurchführung mit
• - einem Raum bis zu Anschlussvorrichtungen (39) für Zuleitungen von Außen,
• - und der Dampfraum (50).

The steam room ( 50 ) is part of the so-called vacuum range ( 30 ) (a region of lower pressure) resulting from having a vacuum pump at one of the liquid surface ( 55 ) farther away the coherent spatial area of air. Belongs to the vacuum area

• - the "vacuum generation zone ( 30 ), Which are generally above a steam cooling range ( 31 ) lies,
• - the distillate collection area ( 40 ) located below the steam cooling zone ( 31 ) lies,
• - The area of the steam passage with
• - a room up to connecting devices ( 39 ) for supply lines from outside,
• - and the steam room ( 50 ).

To the vacuum area ( 30 ) belongs the steam cooling area ( 31 ) with a cooling device at which the steam coming from the heated medium through the vapor passage (which passively follows the pressure gradient in the direction of vacuum) should be cooled and thereby condense. This cooling is generally known in the art as a cooling coil (a coil-like wound glass tube; ). Below this cooling coil is an area ( 40 ), into which the condensate (distillate) can drip in, be collected there and can be removed as a result of the evaporation process.

The two vessels ( 33 ) and ( 32 ) can be coupled together for pressure control in the rotary piston and / or be adjustable in total or individually in height and / or present in a fixed position. In controlling the process over the pressure conditions in the vessels ( 33 ) ( 32 ) could in principle account for the regulation by a height adjustment.

The height of the rotary piston ( 50 ) is due to handling in a defined area and is generally motor assisted (not shown) movable, eg for lowering the rotary piston in a heating bath (not shown) or for general handling such as replacement of the rotary piston. For this is possibly the entire arrangement with rotary piston ( 50 ), Rotary drive ( 51 ) with passage, the cable guides ( 52 ) ( 53 ) and connectivity ( 39 ) for external supply lines ( 42 ) ( 43 ) and also external solenoid valves ( 41 ) ( 45 ) adjustable in height or motor driven (not shown) movable.

It can also be parts of the medium inlet or outlet in height H ( 46 ) or change, but - as described above - are the supply lines and their leadership for the events on the liquid surface ( 55 ) of the medium ( 54 ) Not relevant; only the height differences h ₁ ( 36 ) and h ₂ ( 37 ) are crucial, but must be monitored by means of suitable sensors and controlled by an electronic control.

Once put into operation, flows in with arrangement (modified rotary evaporator) a continuous (medium) stream ( 34 ) from the upper vessel ( 33 ) via a supply line ( 43 ) ( 53 ) directly into the medium ( 54 ) in a rotary flask ( 50 ) and a steady stream ( 35 ) via a derivative ( 42 ) ( 52 ) from the medium ( 54 ) of the rotary piston ( 50 ) back out into the lower vessel ( 32 ). So that the outflow from the rotary piston ( 50 ) into the lower vessel ( 33 ) is not interrupted, the hydrostatic (sub) pressure by the height difference h ₂ ( 37 ) plus the suction effect of the pressure P _suction in the vessel ( 32 ), eg generated by a pump ( 38 ), the suction effect of the vacuum region ( 50 ) exceed.

So that the upper vessel ( 33 ) does not empty, carries a pump ( 44 ) Medium from the lower vessel ( 32 ) upwards into the upper vessel ( 33 ) (possibly via one or more intermediate vessel (s) ( 58 ), into which also new medium can be added to the circulation), thus closing the material cycle of the permanently flowing medium.

In order to be able to separate the evaporation process from the material cycle, at least in the short term, 41 ) ( 45 ) Valves are provided. Due to the above the medium in the rotary flask ( 50 ) vacuum (vacuum) is an additional, the flow ( 34 ) driving pressure difference between the upper vessel ( 33 ) and the rotary piston ( 50 ). It should be noted at this point that in an inventive arrangement of in each case, of course, the total pressure balance in an action branch is to be considered: While a negative pressure in the rotary piston ( 50 ) eg the feeder ( 34 ) from the upper vessel ( 33 ), this negative pressure brakes in the rotary piston ( 50 ) simultaneously the outflow ( 35 ) because of the lower pressure difference, if not in the lower vessel ( 32 ) by means of another pump ( 38 ) also a negative pressure P _suction can be adjusted. The hydrostatic pressure between the medium (surface ( 55 )) in the rotary flask and the lower vessel ( 32 ) from the height difference h ₂ ( 37 ) must be greater than the difference between the negative pressure above the medium ( 55 ) and the pressure in the lower vessel ( 32 ).

The evaporation process is process technically at a set pressure difference and otherwise stable parameters, the physical process requirements following, at a defined temperature of the medium ( 54 ) in a rotary flask ( 50 ) carried out. Temperature and the pressure difference between the vacuum above the medium and the pressure in the medium itself determine the process.

Usually, the rotary piston immersed in the prior art in a heating bath, in which it - as described above - is heated by rotation of passive heat transfer through the glass of the piston away. This form of heating of the medium has the disadvantage that the temperature setting is very slow. The fact that, in addition to the other adjustment or regulation of the pressure difference between above the medium and the interior of the medium, the temperature of the medium in the evaporation vessel is adjusted or regulated here by the medium flowing into the evaporation vessel ( 43 ) by a in the supply line ( 43 ) lying additional heating (not shown here) is heated to target temperature, the evaporation process can be improved in a rotary evaporator with respect to the temperature control.

This heater, which is preferably designed as resistance heating or as induction heating, is supported by a heat pump (not shown), which transports heat energy from the medium flowing out of the vessel onto the medium flowing into the vessel. This requires less energy to heat the medium.

With this much faster possibility of adjusting the temperature of the medium, together with the efficient pressure control, there is no need to set up a parameter setting by means of the vacuum pump. A simple generation of vacuum is sufficient, and thus the way is free to redesign the radiator area according to the invention.

As already stated above for pressure control, the temperature excitation can of course be arbitrary; However, it is necessary for the reorganization of the cooling arrangement according to the invention that the setting of the required P, T process parameters no longer requires that the vacuum area must be adjusted to a precisely set and exactly regulated negative pressure value for this purpose.

Although in this not shown, but in particular the cooling area ( 30 ) with a cooling device in the foreground of interest. That should be based on the be shown in more detail. This shows this to the prior art schematically a cooling device ( 92 ), which will be explained again using the example of a rotary evaporator.

A rotary piston is indicated by a rotary evaporator ( 90 ) in a heating bath ( 99 ) and which by means of a motor drive ( 91 ) in the heating bath. Steam arising in the rotary piston can be conveyed through a steam feedthrough into the upper region of the cooling arrangement (cooling tower) ( 92 ) rising up.

The at the liquid surface ( 93 ) at a defined pressure and temperature (in the prior art by a heating bath ( 99 ) is heated) in a rotary flask ( 90 ) steam flows (passively) from the place of its formation ( 93 ) in the direction of the vacuum, ie in the direction of the falling pressure through the steam passage ( 91 ) through to the cooling area ( 95 ) of the cooling arrangement ( 92 ), where it meets a cooling coil ( 94 ), condenses due to the low temperature at the cooling coil ( 94 ), drips from there and, following gravity, falls down into a collecting device; at least the theoretical construct.

The pressure gradient is in the prior art not only for the process pressure at the liquid surface ( 93 ) of the medium to adjust and maintain suitable, but also necessary for the removal of steam through the steam passage from the rotary piston addition. The vacuum required for this is achieved by means of a vacuum pump ( 98 ) generated in the vacuum region ( 95 ) is pumping out contained air or gases. The connection ( 97 ) for a vacuum pump ( 98 ) to the cooling device ( 92 ) is provided for good reasons usually far away from the place of vapor formation, because no steam should get into the vacuum pump.

So arises in the vacuum area ( 95 ) of the cooling tower ( 92 ) a more or less strong negative pressure (the vacuum). Thus the cooling by the cooling coil ( 94 ) is as efficient as possible, ia through the cooling coil, which consists of a coil-wound tube (often glass in the rotary evaporator), additionally passed through a coolant which is passed in the cooling coil either from top to bottom or from bottom to top. Sometimes at the entry points ( 96 ) of the coolant inlet and outlet sensors provided to close from a temperature difference on the respective amount of heat absorbed.

Such a cooling arrangement is burdened with many problems and disadvantages:

Physically, heat is a movement of atoms and molecules. The physical teaching shows this especially on models with a limited volume in which a gas is located. The movement of the gas molecules represents the heat energy that is given (at a defined pressure) by the temperature.

If the pressure p is low in a delimited area of space V, because there are no or few molecules or atoms (because there is a vacuum) then heat transport can no longer take place or at least only to a small extent. The lower the pressure p of a gas in a given volume V, the lower its temperature T and can be less and less cooled as gas. Cooling a vacuum is simply pointless.

In rotary evaporators of the prior art, however, exactly this is tried. In the generally projecting or vertical cooling tower (made of glass) ( 92 ), in which the so-called vacuum region ( 95 ), the cooling coil ( 94 ) (a spiral of glass with a relatively small surface), through which the coolant - through leads ( 96 ) is accessed from the outside - is pumped to the steam in the cooling tower ( 94 ) in a "vacuum" to cool.

The vacuum is at an upper point ( 97 ) of the cooling tower ( 92 ) by pumping ( 98 ) of the air or gas contained therein, ie the gas in the cooling tower ( 92 ) is thinned up more and more. The generated steam diffuses into this vacuum. Criterion for the beginning of the evaporation process may be, for example, the rise of the vapor at half height in the cooling tower. The set vacuum applied at the location of the vacuum "feed" on the cooling tower ( 97 ) is allowed only be so large that the process parameter "pressure" above the liquid surface ( 93 ) can be stably maintained. This is structurally influenced in the design of the rotary evaporator within limits, but no longer in the operation of the existing evaporator, because due to the vacuum for cooling the steam necessary heat transfer to the cooling coil ( 94 ) gets worse and worse.

Thus there is (also) a (non-optimal) flow in this area with opposite effects: The pressure gradient has to be as large as possible for effective steam transport, which means in the cooling tower ( 94 ) or in the vacuum range ( 95 ) but also towards the top or in the upper part of the cooling tower getting worse cooling, since the heat transfer with decreasing pressure is getting worse.

Processually (and also energetically) it would be better, the removal of steam from the interior of the rotary piston ( 90 ) to operate actively under energy use, to suck the vapor and compress, which would take place under temperature increase (by compression or compression of the steam) to cool the compressed steam then aggressively and then release with expansion in the catchment area. During expansion, the vapor would continue to cool, condense very quickly and be present as a distillate. The risk of re-evaporation would not even emerge and the inefficiency of the cooling coils ( 94 ) at low pressure in the vacuum range could be avoided.

However, this possibility, which is considered to be a preferred first construction, requires relatively far-reaching design measures due to special valve designs. Therefore, in addition to this first possibility according to the invention, a second possibility according to the invention is first presented here, which to a certain extent works by exchanging and reversing the functions of the components of the cooling arrangement and can also be realized with the simple means of a laboratory.

shows this second inventively retrofitted evaporation arrangement on the basis of a rotary evaporator, in which iW only the previously involved components of the cooling device of the prior art are shown. However, the condensation is more efficient than in the prior art by a function exchange according to the invention and pipe modification of the steam removal.

The comparison with shows that here in a rotary evaporator is present, with a rotary flask ( 60 ) with a medium ( 69 ) and an indicated rotary drive which has a steam feedthrough, through the steam formed in the evaporation space to an indicated connection device ( 72 ) can get. This connection device ( 72 ) puts the in With ( 31 ) ( 30 ) designated and indicated beginning of the vacuum region, with the in the vacuum area ( 95 ) of the cooling device begins.

The functionality of the vapor formation and propagation is in this arrangement to the connection device ( 72 ) with the to the and described functions comparable.

The two lines ( 70 ) ( 71 ) passing through the area of the necessarily existing steam feedthrough ( 84 ) must be guided through and already the described supply line ( 70 ) of medium or derivative ( 71 ) of medium in / out of the medium ( 69 ) of the rotary piston in / out and thus the formation of the medium circuit for the pressure control in the medium ( 69 ), indicate here only the one part of the modifications of a rotary evaporator according to the invention, which will not be considered further here; here in a modification of the invention, the cooling device in comparison to a cooler assembly of the existing prior art of being represented:

Also in this arrangement the is with a vacuum pump ( 68 ) creates a vacuum by evacuating or pumping out air from the vacuum area ( 79 ). The withdrawal of the air originally located in the vacuum region to form a negative pressure (vacuum) takes place here via a line ( 67 ) (to which the vacuum pump ( 68 ) is connected via a distillation collecting space ( 76 ) ( 78 ), from below through the interior of a cooling coil (also available here) ( 64 ) (or a cooling tube), so led upwards and on top of a connection ( 73 ) of the described connection device ( 72 ), so that also in the rotary piston ( 60 ) above the liquid surface ( 63 ) creates a negative pressure.

The requirements for the constancy of this vacuum are low.

The main difference to the cooling arrangement of (Prior art) is that the vacuum and thus the steam is passed from top to bottom inside the cooling coil; a coolant used here as well ( 65 ) surrounds the outside of the cooling coil. Basically, the structure according to the invention of a cooling arrangement thus also corresponds in general to the structure of the prior art; but through the area of the cooler in which in the prior art, a vacuum was present or in which the incoming, was to be cooled steam is now conducted coolant and where in the prior art, a coolant has flowed (in the cooling coil inside), is now a portion of the vacuum area through which the steam to be cooled is passed.

The coolant used in each case is stored in a container or a storage area ( 80 ), in which the coolant itself can be kept at a low temperature by conventional methods (refrigerator or, for example, a simple ice-water mixture). It is by means of a pump ( 74 ) in a circuit via supply lines or connections ( 66 ) on the outside ( 65 ) of the cooling coil ( 64 ), in the lower part of the radiator ( 85 ) and via a line ( 81 ) back into the container or storage area ( 80 ) returned.

The vacuum is as before by means of a vacuum pump ( 68 ) produced by the fact that from the entire together and adhering space, the air present there or the existing gas is permanently pumped out ( 79 ). The vacuum pump may be, for example, a simple water jet pump or another, also higher-valued controllable vacuum pump.

Above the liquid surface ( 63 ) will create a negative pressure in this way, which by a suitable adjustment of the pumping power of the pump ( 68 ) can be stronger or weaker and to a vacuum suitable for the evaporation process above the liquid surface ( 63 ) can be adjusted. Controlled by pressure setting in the supply line ( 70 ) and / or in the derivative ( 71 ), the pressure difference between the interior of the medium ( 69 ) and above the surface ( 63 ) are set accurately and very quickly for the evaporation process.

Due to an additional heat supply, as usual by a water bath from below (not shown) or by a directly in the medium supply line ( 70 ) lying heater, which can be designed as resistance heating or as induction heating (not shown), the medium ( 69 ) is heated to process temperature.

At the temperature thus given or set and under the pressure conditions thus given or set, the evaporation process proceeds as usual, steam is generated and is transported away in the direction of the falling pressure, flows through the area of the motor drive ( 61 ) with a steam feedthrough via the connection points ( 72 ) ( 73 ) (with progressive compression by the narrowing lines) the cooling coil ( 64 ).

Due to the progressive compression by the narrowing lines increases with the compression of the gas (according to the general gas equation pV = RT), the gas temperature of the steam initially significantly, which facilitates the heat transfer from the steam over the material of the cooling coil on the coolant on the cooling coil on the coolant which makes the cooling of the steam more efficient. That in a cycle ( 80 ) ( 74 ) ( 66 ) ( 77 ) ( 65 ) ( 85 ) ( 81 ) ( 80 ) guided coolant decreases in area ( 65 ) of the cooling coil ( 64 ), a larger amount of heat energy coming from the steam than is possible in the prior art, in which, formulated somewhat exaggerated, trying to cool a vacuum.

After the steam, after the passage of the cooling coil now cooled but still slightly compressed, ie standing under a slightly higher pressure, the radiator region has left, this steam meets an inventively provided significant increase in line ( 78 ) with the subsequent catchment area ( 76 ) for the distillate. The steam expands here, with further pronounced cooling, in the close of the vacuum pump ( 68 ) generated negative pressure area ( 78 ) ( 76 into it; it also condenses the last residue of steam, which may still be present, and drips as condensate / distillate ( 75 ) in the collecting container ( 76 ). In the steam flow path behind the collecting container ( 76 ), ie in the area of the hose / pipe guide ( 67 ) the air is essentially dry.

Since the vacuum will also be pronounced here, it may be useful to place the distillate in the collecting container ( 76 ) to exclude any re-evaporation. This can be achieved by routing the coolant around the collecting container ( 76 ), but is generally not necessary due to the previous expansion cooling.

The steam flow direction ( 62 ) through the cooling area in an arrangement according to the invention from top to bottom, in order to be able to take along a condensate already formed on the cooling section and down into the collecting area (FIG. 76 ) to flow.

The direction ( 77 ), in which the coolant flows, although here also from top to bottom, this direction could also be reversed. Under consideration of constructive conditions and a variable thermal management, which may include other components of the entire evaporation arrangement and possibly also heat pumps, both can be useful.

In the illustrated cooling coil ( 64 ) is for the comparative representation of the same shape and length, as in illustrated in the prior art, but actually does not need to be very large and long designed in an inventive arrangement. Depending on the size of the evaporator, a fairly short piece of hose or pipe (smooth or meandering or spool-like as shown by the coolant) may suffice, as the cooling process is so efficient.

shows the first inventively retrofitted evaporation arrangement, is operated with the rectification or one-way valves and by means of a special cylinder-piston pump, the steam removal active. The components (without a vacuum pump) of the previously described are in this contain the same identifiers. The rotary piston, the condenser, the circulation of the coolant, the distillate collection area correspond to the arrangement of , That to therefore also described here; However, the vacuum pump is omitted.

In the line from the rotary evaporator with the steam guide from the connection points ( 73 ) to the line ( 146 ) or junction on the radiator is now a pump assembly (total with 140 with which both the vacuum for the evaporation zone ( 60 ) is generated in the rotary piston, as well as the steam is actively compressed and passed through the radiator assembly (possibly necessary buffer tank are not shown)

The pump ( 140 ) consists of a pump cylinder ( 148 ), in which a piston ( 143 ) driven by a motor (not shown) can be moved back and forth. During this movement, eg from right to left, the cylinder space decreases ( 144 ) on the one side, the cylinder space on the other side of the piston ( 143 ) increases. Valves that allow only gas or air or vapor to pass in one direction are indicated by triangular symbols ( 141 a - d ) indicated. Gas or air can flow only in the direction in which the respective triangle points like an arrow (here always from top to bottom)

Steam over the pipe ( 73 ) coming from the rotary piston is a common upper cavity ( 142 ) and can this cavity ( 142 ) only via one of the two valves ( 141 a . b ) leave again. If the piston moves ( 143 ) to the left, this increases the pressure in the decreasing left cylinder space ( 144 ), the valve a closes and thus prevents the steam from flowing back up through this valve a; the steam can - under compression - this cylinder space ( 144 ) only via the valve c into another cavity ( 145 ) into which the steam is to a certain extent forced in through the valve c open in this direction (whereby the steam is compressed).

Meanwhile, in the opposite cylinder chamber, which increases and generates a prevailing negative pressure, steam is applied via the valve ( 141 b) sucked while the valve d closed by this pull.

With the backward movement of the piston ( 143 ) (now moving from left to right) increases the cylinder space ( 144 ) there is now a suction there, which opens the valve a and closes the valve c; now steam is coming out of the room ( 142 ) via the valve a into the cylinder space ( 144 ) sucks it in.

While so permanently steam (with gas, air) from the cavity ( 141 ) is sucked (no matter in which direction the piston is moving), whereby in the cavity ( 142 ) a vacuum, which into the rotary evaporating flask ( 60 ), and thus arises above the liquid surface ( 63 On the other hand, the steam is compressed by means of the piston movement in the other half of the cylinder in the direction of the cooler and into the cavity (FIG. 145 ) pumped. The thus already compressed steam is passed on to cooling, where the already to described process causes the distillate.

The vapor flow direction ( 65 ) from top to bottom is not absolutely necessary in this arrangement, but makes sense here as well, because thus the direction of the dripping distillate ( 75 ) coincides with the direction of progressive steam cooling. If the steam at the lower end of the cooling coil (which cools down through the line in the cooling coil with cooling through the coolant surrounding the cooling coil) will cool down again. The now dripping distillate ( 75 ) is no longer really at risk of back vapor.

However, in the place of steam expansion ( 78 ) now a ventilation ( 147 ), which can be achieved, for example, by a riser (possibly also higher than shown).

The remaining components of the cooling arrangement correspond (with the same identifiers) those of with the respective coolant used in a storage area ( 80 ) by means of a pump ( 74 ) in a circuit via supply lines or connections ( 66 ) on the outside ( 65 ) of the cooling coil ( 64 ) and at the bottom of the radiator ( 85 ) and via a line ( 81 ) back into the container or storage area ( 80 ) is returned. The to given description also applies here.

At this point, it should be noted once again that the outdoor area used in the prior art as a vacuum area ( 65 ) of the cooling coil ( 64 ) (in which so far the steam rose to cool) now according to the invention with coolant ( 65 ) and that the coolant ( 65 ) now the cooling coil no longer flows through the inside, but lapped from the outside.

However, the area through which the coolant flows no longer has to have the large volume originally provided for the vapor rise: in a construction according to the invention, it is sufficient to provide a very small volume for this exterior space. In principle, a cylindrical coaxial design will suffice with an inner pipe (for the steam or the coolant) and an outer pipe (for the coolant or steam) lying around it. However, the usual image of a rotary evaporator with a cooling coil could be maintained so sales support.

Also, the length of the cooling coil can be designed much smaller than was necessary in the prior art; In principle, it is sufficient for a short distance of a cooling tube, which is lapped by coolant, and possibly only to the with the expansion at the end of the cooling section ( 78 ) To prepare only very strong connected cooling so to speak.

That the evaporation vessel ( 60 ) does not necessarily have to be the rotary piston of a rotary evaporator, but in another evaporation arrangement a very different evaporation vessel can be used, for example a beaker on a magnetic stirrer, but in the same way the removal, the cooling of the vapor and the collection of the distillate can take place shows that the invention is not limited to rotary evaporators, but can generally be used in evaporator arrangements in which hitherto the removal of the steam was passive in that the steam had to passively follow a pressure gradient.

When using a beaker as an evaporation vessel (with an upwardly sealing lid) on a magnetic stirrer, e.g. the stirring mechanism of the magnetic stirrer (a stirring body coupled to a magnetic drive) is used as a replacement for the rotary movement of the rotary piston and the heating by the heatable mounting plate of the magnetic stirrer as a replacement for the heating bath in a rotary evaporator. Other constructions are conceivable.

However, efficient cooling of vaporization vapor to obtain and collect condensate is more efficient with the process of the invention as a principle than in the prior art vacuum-controlled cooling tower in which a cooling coil is intended to cool the rising vapor.

Claims (10)

A method for cooling the resulting in an evaporation in an evaporation arrangement for the separation of a liquid component from the medium (a liquid mixture) resulting vapor, characterized in that the resulting vapor in the interior of a cooling tube or a cooling coil (64) is transported away with increasing compression and cooled, and for cooling a coolant (65), the cooling coil (64) flows around from the outside. Method according to Claim 1 characterized in that evaporation arrangements are used for separating a liquid component from the medium (a liquid mixture) comprising - an evaporation vessel with an evaporation space into which the medium to be evaporated is introduced, - at least one possibility, in the evaporation vessel, the pressure difference between the interior of the medium and the gas pressure over the medium (setting the pressure), - at least one way to heat the medium to a process temperature (setting of the temperature). Method according to Claim 1 or 2 , characterized in that evaporation arrangements for the separation of a liquid component from the medium (a liquid mixture) are used which have means for regulating and / or adjusting the parameters of the evaporation process, in particular for adjusting the temperature and the pressure. Method according to at least one of Claims 1 to 3 , characterized in that Evaporator assemblies for separating a liquid component from the medium (a liquid mixture) are used, which use as evaporation vessel - Rotary flask of a rotary evaporator or - Erlenmeyer flasks or beakers (with a suitable lid) on a magnetic stirrer or - a pots (with suitable lid) on a hearth. Method according to at least one of Claims 1 to 4 , characterized in that evaporation arrangements for the separation of a liquid component from the medium (a liquid mixture) are used, which use an evaporation vessel, which is integrated in a medium circuit through which the pressure conditions can be adjusted in the evaporation vessel. Method according to at least one of Claims 1 to 5 , characterized in that a cooling device with respect to the steam transport direction (62) to the end of the cooling coil out there or generated there vacuum (68) through the interior of the cooling coil (64) such that the at the beginning of the cooling coil (73) generated steam , which follows the pressure gradient, is transported inside the cooling coil under compression from top to bottom, so that condensate / distillate resulting from the cooling can flow downwards into the collecting vessel (76), following gravity. Method according to at least one of Claims 1 to 6 characterized in that in a cooling device with respect to the steam transport direction (62) at the end of the cooling coil and to the vacuum source (68) close to the collecting vessel (76) for the distillate (75), the steam-conducting transport tube is widened (78), to rapidly cool and condense the incoming and compressed steam through expansion. Method according to at least one of Claims 1 to 7 characterized in that in a cooling device the cooling coil or cooling tube is designed as a cylindrical coaxial construction with an inner conduit for the vapor or coolant and an outer conduit for the coolant or vapor lying around it. Method according to at least one of Claims 1 to 8th , characterized in that in a cooling device by means of a cylinder-piston pump (140) in which a piston (143) in the cylinder is tightly moved back and forth, so that the cylinder chambers (144) on the two sides of the piston (143) are alternately reduced in size and enlarged, and valves that only allow vapor to pass in one direction are used to continuously draw vapor from the direction toward the vessel, and are compressed and pumped towards the radiator to absorb the suction effect Evaporating vessel to generate the required negative pressure and at the same time to transport steam with further compression in the direction of the cooling device. Method according to at least one of Claims 1 to 9 , characterized in that evaporation arrangements for the separation of a liquid component from the medium (a liquid mixture) are used, which use an evaporation vessel, in which a coupled with a magnetic drive stirring body is used.

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